Mechanical properties of keratin fibres between −196°C and 20°C

Dynamic mechanical loss in keratin at low temperatures

“…A recent publication (6) has established that the//-transition is intimately related to the presence of water in the disordered fraction of the keratin. To delineate the observed differences between the two forms of keratin in fig.…”

Temperature-dependent dielectric properties of slightly hydrated horn keratin

“…The nature of keratin has been the subject of numerous investigations involving host of experimental techniques such as mechanical properties [4], dynamic mechanical loss [5], differential scanning calorimetry (DSC) [6,7], conventional and advanced microscopic techniques like optical microscopy, scanning electron microscopy [8], transmission electron microscopy and atomic force microscopy [9], spectroscopic techniques like nuclear magnetic resonance (NMR) [10], Fourier transform infrared (FTIR) and Raman spectroscopy [11,12], NIR spectroscopy [13], ellipsometry [14,15], structural techniques like conventional X-ray diffraction [16,17] and that employing synchrotron radiation [18,19] and various electric and dielectric techniques [20][21][22][23][24][25][26]. Mechanical [27][28][29], electrical [20][21][22][23][24][25][26] and thermal [6,7] properties of keratin have been found to strongly depend on the amount of moisture in the sample and hence it is important to understand the exact nature of bound water in keratin.…”

Water in keratin. Piezoelectric, dielectric, and elastic experiments

“…Speakman (10) substance or matrix. The microfibrils are -72-76 A in and Druhala and Feughelman (11) measured hydration diameter and spaced -86.5-97.5 A apart (1). X-Ray and temperture dependence of the rigidity of keratin to analysis and electron microscopy have demonstrated the discuss actions of water in it.…”

“…, a and b, shows temperature dependence of the elastic constants c' and the loss c" of horn keratin with various hydration levels(21,17,14,11,8, 5% m.c. and oven dry).…”